We see a ton of cars come in with tires that are older than 10 years – and while the tread looks brand new, we HIGHLY recommend replacement to the customer with a blank stare given in return. Most auto manufacturers recommend replacing tires after 6 years – even if they have 1 mile on them.
Rubber degrades, belts separate – and this leads to tire failure. Tires are not a profit center for our business, so when we recommend replacement, it’s not money we’re after- we like our customers to be safe…
Here’s an interesting read about this subject that breaks it down well from Edmunds.com.